Radiant heater



p 1950 w. E. SCHMERTZ 2,951,476

RADIANT HEATER Filed Aug. 27, 1956 INVENTOR? WILLIAM E SCHMERTZ. BY l w ATTORNEY? United States Patent Oficc Patented Sept. 6,1260

This invention relates to a radiant heater, and more especially, relates to a radiant heater specially designed for use in mills, factories, out-of-door work areas and similar places where workmen exposed to cold weather are to be provided with some heat but wherein no attempt is made to specially heat the entire atmosphere. It is intended for use primarily in location where so-called salamanders are commonly used to provide warmth, and is designed to give more heat more effectively andwith less floor area. a U

My invention has for its object to provide a more effective heater of this type which will be relatively light, cheap, inexpensive, effective and which will have a long serviceable life. My invention relates especially to. the reflecting hoods for such heaters.

My invention may be more fully understood by reference to the accompanying drawing inwhich: j a Y T Fig. 1 is a vertical'section through a heater embodying my invention; and a a 7 Fig. 2 is an elevation of the heater.

The heater comprises a thin stainless steel cylinder or tube 2 the length of which is many times its diameter. It is encircled by strap-like metal collars 3, 4 and 5 and these are connected by a plurality, preferably three narrow metal bars 6, the lowermost ends 7 of the bars flaring outwardly from the lowermost collar 5 to provide a tripod support for the heater, the bars giving vertical stifiness to the thin metal cylinder but having little surface area so they present a minimum area to the radiation of heat from the shell to a by-stander. They are also out of contact with the tube so that the conductive heat area is at a At the bottom of the tube 2 there is a gas or other fluid fuel burner, 8. This is preferably a plate or star type burner producing a multiple number of small flames over a large area. A mixer tube for the burner is indicated at 9.

The top collar 3 has radial upwardly sloping arms or braces 10 thereon which are secured to the inwardly turned peripheral flange 11 of a cylindrical sheet metal hood 12, the top of which is designated 13. The various parts of the structure may be secured together in any suitable fashion, and in the drawings rivets have been shown to indicate this.

Within the hood 12 is a molded reflecting body 14 of refractory heat-reflecting material. It may comprise a bonded body of ordinary Portland cement and sand through which are distributed stainless steel shavings such as result from the grinding of stainless steel ingots to remove surface defects, these shavings or particles being available in great quantities in stainless steel producing areas. The shavings are principally in the form of short fibers mixed with smaller particles or granules and may even contain some spent abrasive. They are individually of small mass, highly reflective to heat and good conductors but highly heat resistant. I may make a mix of Portland cement and such shavings, with or without sand and wet with water. This is molded into the hood 12 before the hood 12 is assembled on the heater and while it is in- 2 r verted to the position shown in the drawings. -Its exposed area is preferably concaved, as indicated at.15 and 1t 1s molded so that its periphery is thick enough to fill thespace between thelip or flange 11, so that the flange re tains the mass in place when the hood'is invertedfor use.

Instead of using Portland cement, fire clay or refractory cement may be used, either being preformed and fired be-' fore being placed in the hood or being baked after it is formed in the hood and hardened by heat when used. Only suflicient cement or cement and sand is' used to form a bond for the mass of metal particles, which for example may be 50% to 60% by bulk of the entire mass, or even more. a

The overall height of the heater may be of any desired dimension but is preferably of the height of an average man or greater while the diameter may be of the order of eight to ten inches. In use the gas burner operates at a high rate of fuel consumption, and because of its thin structure, the tube 2, which operates as a flue to induce a rapid flow of hot gases through it, reaches a glowing temperature, very quickly, normally operating with a dull red glow. Because it is thin and is of good conductivity, the glow is reasonably uniform from top to bottom, so that it is an effective heat radiator to persons or objects in its vicinity. V V a 7 Much heat is carried out the top of the fine 2, and this impinges against the under face of the mass 14 within the hood. The entire mass quickly heats and the metal particles at the surface glow. The heat that would otherwise be lost for all practical purposes is radiated to the floor area around the heater. Thus it serves to warm the floor on which workmen stand and to warm their feet or objects which they may have to handle in thearea at or above the floor level. v

While/l have used stainless steel wool packed into the hood with reasonably satisfactory results, it does not fully meet the requirements of the heater because it does not produce the desired spread of heat, and the refractorymetal filled body is superior to a sheet metal reflector at this location. Also, since the metal shavings and chips used with my invention are a waste product from which there is little gained by remelting, their use is more economical as well as more eifective than either stainless steel wool or sheet metal reflectors.

The refractory composition of earthen material, such as cement, fire clay, is in itself a highly useful material containing metal shavings or chips, which in addition to being used in the hood of the heater, can also be used in other places and formed into other shapes. In the form of bricks, for example, it may be used in checker work of regenerators, in firepots and elsewhere where heat absorbing and emitting properties are required. Such brick has a peculiar advantage in checkers since the checkers, when discarded, can be used in a melting charge with the cement forming a flux and the metal recovered.

In the construction here shown, the vertical bars 6 carry the load of the hood so that the support of its weight is not imposed on the radiant tube.

I claim:

1. A radiant heater for use primarily in otherwise unheated environments for warming workmen in the vicinity thereof comprising a sheet metal tube of uniform diameter of the order of 8 to 10 inches, which tube is formed of stainless steel and is of an overall height at least as great as that of an average man, the lower end of the tube being in proximity to but elevated above the floor on which the heater is placed, a supporting structure for the tube having legs extending downwardly from adjacent the lower end of the tube to the floor for supporting it and elevating its ,lower end above the floor, a burner in the bottom of the tube for projecting a column of flame up the interior thereof and against the walls of the tube for causing the tube to incandesce, the exterior of the tube being substantially exposed whereby heat may be radiated therefrom to persons in proximity thereto, and a heat-reflecting hood carried on fixed supporting means secured to the upper end of the tube, said supporting means comprising upwardly divergent spaced arms at intervals around the tube projecting above the top of the tube, the under surface of the hood being concaved and of substantially larger diameter than the tube, said under surface being in position to be contacted by flames emerging from the top of the tube and to radiate heat absorbed therefrom to the floor area immediately around the base of the tube;

2. A radiant heater as defined in claim 1 wherein the hood comprises a formed body of imperforate earthen material and stainless steel particles and fibers, and a shell. containing the body, the arms being attached to the shell.

3. A heater of the class described comprising a pair of upper and lower hoops, a plurality of fiat parallel bars extending from one hoop to the other andattached to the exterior thereof, divergent legs extending downwardly and outwardly from the lower hoop, each leg being attached to a bar where it is secured to the hoop, the vertical distance'between the hoops substantially exceeding the vertical distance from the lower hoop to the lower ends of the legs, said vertical distance also being many times the diameter of the hoops, a sheet metal tube of uniform diameter fitted into and secured to the hoops with its lower end projecting downwardly below the lower hoop and terminating above the lower ends of the legs, a plate type gas burner supported at the bottom of the tube ofan effective area substantially as great as the interior diam eter of the tube for generating a column of flame in the tube which fills the tube, a hood of greater diameter than the tube over the upper end of the tube, and brackets extending at spaced intervals upwardly from the upper hoop supporting the hood in spaced relation to the .top of the tube, said hood having a concaved heat radiating under surface of larger diameter than the tube.

4, A heater of the class describedcomprising a supporting frame formed of a plurality of metal bars extending vertically in substantially equally spaced relation about bars are arranged, a burner supported on the inturned ends of the bars, a sheet metal tube of uniform diameter fitted into the hoops and extending from about the top of the burner to the top hoop, said vertical bars being spaced from the surface of the tube by the hoops, diverging legs extending downwardly from the lower hoop at intervals thereabout, and a hood of greater diameter than the tube over the upper end of the tube, and brackets extending at spaced intervals upwardly from the upper hoop attached to the hood and supporting it in spaced relation above the tp of the tube, said hood having a concaved heat-radiating under surface of larger diameter than the tube.

5. A heater of the class described as defined in claim 4, saidhood having an exterior shell above the heat-radi-- ating under surface and which is concaved; j

Re ferences Cited inthe file of this patent I UNITED STATES PATENTS 

